Tera-Scalable Algorithms for Variable-Density Elliptic Hydrodynamics with Spectral Accuracy

We describe Miranda, a massively parallel spectral/compact solver for variabledensity incompressible flow, including viscosity and species diffusivity effects. Miranda utilizes FFTs and band-diagonal matrix solvers to compute spatial derivatives to at least 10th-order accuracy. We have successfully ported this communicationintensive application to BlueGene/L and have explored both direct block parallel and transpose-based parallelization strategies for its implicit solvers. We have discovered a mapping strategy which results in virtually perfect scaling of the transpose method up to 65,536 processors of the BlueGene/L machine. Sustained global communication rates in Miranda typically run at 85% of the theoretical peak speed of the BlueGene/L torus network, while sustained communication plus computation speeds reach 2.76 TeraFLOPS. This effort represents the first time that a high-order variable-density incompressible flow solver with species diffusion has demonstrated sustained...

• Type: Conference
• Year: 2005
• Where: SC
• Authors: Andrew W. Cook, William H. Cabot, Peter L. Williams, Brian J. Miller, Bronis R. de Supinski, Robert K. Yates, Michael L. Welcome
• Keywords: Applied Computing, Incompressible flow, Miranda Utilizes Ffts, SC 2005, Variabledensity Incompressible flow